电场对Al-Mn-Mg合金的微结构和织构形成的影响

利用透射电子显微镜观察(TEM)和X射线衍射技术(ODFs分析),研究了电场对Al-Mn-Mg合金的回复和再结晶组织演变、再结晶织构的形成和发展的影响.结果表明,电场对再结晶的影响其强度有一个门槛值(3～4 kV/cm),低于此值电场对该合金的再结晶没有明显的影响.强度为4 kV/cm的电场对再结晶形核的影响较大,可抑制Al-Mn-Mg合金的回复和再结晶,促进再结晶立方织构的形成.其主要原因是电场降低了各取向的形变储能,推迟了再结晶进程,抑制储存能小的取向晶核的形成和长大,促进储存能大的S取向晶粒向立方织构择优生长.

Microstructure and textures variation of Al--Mn--Mg alloy sheets under external electric field

The effects of electric field on recovery, recrystallization and textureof cold rolled Al--Mn--Mg alloy sheets were investigated by TEM and X rayanalysis (ODF). The results show that when the intensity of electric fieldchanges between 2 and 3 kV/cm, the electric field has no obvious effecton recrystallized progress of the cold--rolled Al--Mn--Mg alloys sheets. Whenthe intensity of electric field was 4 kV/cm, it retards the recovery andrecrystallization significantly. So It is believed that there is athreshold value (3 $sim$4 kV/cm ) which decides the effect of electricfield on recrystallization. The effects results from that the electric fieldretards the mobility of dislocation. Furthermore, the electric field annealingreinforce the cube texture of this sheet.